Machines for packaging products such as beverage cans, or bottles in paperboard cartons are known in the art. Typically, a conveyor system transports the products to be packaged toward a loading mechanism which can push the products into open ends of a partially constructed carton. As the loaded carton is transported further along the conveyor path, an adhesive, such as hot glue, is applied to flaps of the open carton ends, which are then pressed closed by structures or mechanisms further down the conveyor path from the glue applying mechanisms of the machine. The packed and closed carton can then be shipped for retail sale.
Packaging machines are generally designed to handle certain carton configurations. Adjustable elements provided on the machine allow for some reconfigurations of the machine, but cartons packed by these reconfigurable machines usually share certain characteristics required for the machine to be able to successfully pack and close the cartons. Given the size, cost, and complexity of these machines, it is advantageous to design machines that are as versatile in their compatibility with varying carton configurations as possible.
Designing reconfigurable machines poses challenges beyond just creating machines that will successfully pack and load a carton traveling from loading mechanisms through gluing mechanisms and past closing mechanisms in a continuous pass. In some circumstances, the conveyor machinery may be stopped while there are cartons in various stages of packaging. The conveyor may be stopped, for example, at end of a worker's shift, at the end of a work day, or because of an issue occurring along the conveyor path, such as a misfed carton. Such a conveyor stoppage is referred to herein as a “cycle stop.” In these instances, there can be cartons along the conveyor path which have had glue applied to their end flaps, but have not yet had their end flaps pressed closed. During the delay between the application of the glue and the restarting of the conveyor, the glue can cool or cure, preventing adhesion of the end flaps. Merely restarting the conveyor will lead to the end of these cartons being pressed closed, but if the glue has already set and/or cured, carton construction may be unsuccessful.
Some packaging machine designs include cycle stop functions that can be operated to successfully close these cartons following a conveyor stoppage, prior to the glue cooling or curing. A versatile carton packaging machine design, therefore, also requires that cycle stop functions of the machine be compatible with the various carton configurations packaged by the machine.
Generally, the end flaps are the elements that are manipulated as the carton is packed, glued, and closed. The end flap dimensions of certain carton configurations can pose difficulties in versatile packaging machine design. For instance, some packaging machines are designed to be reconfigurable to glue different end flap configurations by selectively deactivating one or more glue guns, which often causes the deactivated glue gun to clog after a period of nonuse. Some difficulties are great enough that certain carton configurations must be hand packed. Such manual processes add considerable time and expense such that these cartons may be used less commercially than they would otherwise be if the packaging process could be automated.